Dynamometer



June 13, 1950 H. M. MARTIN DYNAMOMETER Filed April 7, 1944 /0 Inventor-Haold M. Mrtn,

ttoTTwey.

Patented June 13,* 1950 to General Electric C NewYork (omlv'lan'y, acorporation oi' My. invention relates to improvements in dyn'amor'netersand more Vparticularly to a'd dynanioineter adapted to measure orindicate the torque of a 'machine having a vertically extending shaft.However, the advantages inherent'in my invention apply equally tohorizontal operation.` 4HThisl application is a continuation-impart Aofmy abandoned patent application Serial No. 456,878, le'd September 1,1942,' and assigned to the assignee of this application.

j An lobject of my invention is to provide an improved dynamometerconstruction forY measuring torque.

` :"Another object of my 'invention isto provide an improved dynamometerfor measuring the torque of a machine and for transm'ittingtheV power ofing, and the features of Vnovelty which characterize my invention willYbe pointed'out with particularity in the claims annexed' to and formingpart of this specification.

'In` the drawing, Fig. t1 is' a side elevational view of an embodimentof my improved dynamometer construction, partly broken away and partlyin section to illustrate the details of thetorquetransmittingconstruction; Fig.` 2 is an en d elevational View ofthe dynamometer shown in Fig. -1- partly broken away to illustrate "thearrangement of the torque-measuring device used in combination withthe'torque-transrnitting mechanismshown in detail in Fig. 1, and lookingat -lig. 1 in the direction shown by the arrow; Fig.

'3 is a partial plan view of the construction shown inFig. 2v showingthe supporting arrangement and equalzing motor andcontrol; and Fig. 4 isa schematic diagram of the equalizing motor and control. v

',Referringto the drawing, I have illustrated a dynamometer particularlyadapted to measure fthe torque of a machinehaving a vertically extendingshaft. The torque `from a source of mechanical power provided by thevertically extending shaft of a machine is adapted to be measured bycoupling such a shaft'to a vertically downward extending shaft IIJ ofthe dynamometer, and this shaftis rotatably supported in a bearinghousing I I by a pair of anti-friction ball bearings I2 and I3.f Powermay be transmitted from the shaft I to a load through'a second shaft I4rotatably supported substantially at right angles to the shaft I0 by apair of anti-friction ball bearings I5 and* I6 mounted in the bearinghouslzio ,vided betweenthe shaftsflll and I4 by a setof bevel gears Ijland [8 secured to the shafts IIJ and AIgljrlspectivelv,4 to transmit-power from theverti cally .extendingshaft' I0 tothe horizontallyextend'ingshaftf I 4, or vice versa. A load is adapted togbe :placedwonthe dynamometer through the slkia'ft, Iii' andthe outer end of the shaftI4 is .prof videdwith a 'suitable coupling' which includes [a yoke "I9connected to a Vtorque-transmitting cou-y plingV `link 201 through apivot pin 2| whichis pivotally mounted in the'yoke I9. This pivot pinil]ffforrnsY a .pivotalconnection with vva comple'- ifnent'aryfpivotpiri 22 pivotally mounted in a yoke 23 'secured'to 'the er1d` of thecoupling shaft 20,' thereby providing a 'substantially vuniversal con'-nectinbetween thevyoke vI!! on the'shaft I4 and thefpouplixigshaft'ZU.The coupling shaft 20 is adapted tofpr'ovide ai driving connectionbetween the shaft I4 and a` driven load in order to load the' machineconnected to the inputshaft Il] of the ',dynamoineter, or vice versa.As'shown in Fig. 1; ,the 'en'd of "the coupling shaft 20 away fromthebearing housing' I I also provided with a. yoke 24 secured to 4the endthereofwhich pivotally supportsgawpivpt` pin 25 having" a pivotalconnection with apivgtpin 26 pivotally mounted in a comepl'ementaryyokeZ'l. Slight variations in the disftance betweenjthe yokes23 and 24 resulting from thel turning' of the housing I I `arecompensated for .bl/.D'IOvidingany' suitable longitudinally slidableVconnection between the ends of the coupling shaft 'and-the hub of vtheyokes 23 and424, suchas'lon# gitudin'lally slidable splined connectionswhich will prevent; relative rotation betweenA these partswhile'ipermitting relative longitudinal movement thefr ebe'tween.` Theyoke 2l is adapted to be-se- 'curedt'oi any suitable loading device;such-asa isliaft 28-of an electric generator 29 adapted to be "mountedin any conventional manner to prevent 'rotation thereof around the axisof the gear cas# ing If I and` which can provide acontrollablevariableyload for the machine, or can be used asfa motorforf driving the dynamometer shaft I0 'through theg'earing- I1 and I8.AI f In order to measure'the torque transmitted by thf'shaft ID, thebearing-housing II is rotatably fs'upported on a stationary frame 3U byanupper ball'bearing 3| anda lower journal and thrust ballbearing 32arranged about upper and lower 1li-ubs 3'3 and 34, respectively, of thebearinglousling; so-that the bearing housing II is free to rotatel abouta vertical axis corresponding to the aixisf'pf the shaft I0. With suchan arrangement, substantially noi torque is transferred from the 'ShaftlIIJ through the bearings I2 and I3v to the ing II.-fA*power-transmitting: coupling is pro- 65 bearing housing I I. vHowever,Va consideration 3 of the forces exerted by the shaft I4 on the bearinghousing II indicates that the bearing housing II must provide aresisting torque reaction equal and opposite to the torque transmittedby the shaft I4 in order to prevent the rotation of the shaft I4 aboutthe axis of the shaft I0 or the vertioal axis of the bearing housing II. Thus,A if no load is transmitted between the shafts I and I4 thesetwo shafts merely rotate freely in their bearings supported by thebearing hous-. ing II. If the load on the shaft I4 were to be consideredof such a magnitude as to stallY the source of mechanical powerconnected to the shaft I0, the connecting gears `Ij1jand I18 might beconsidered as being locked with respect to each other. Under suchcondition, the shaft `downward force to the link 58 and to the springbalance scale 59 and the balance mechanism 60 IU would tend to rotatethe shaft I4` about. the

axis of the shaft I0 and, consequently tend. to, rotate the bearinghousing II about the axis 'of the shaft I0. For any transmitted load onthe shaft; I4, there would be a corresponding transmitted torquereaction of the shaft I4 on the bearing housing I I with a complementaryresisting torque reaction of the bearing housing II on the shaft I4 toprevent the shaft I4 from rotating about the axis of the shaft I0. Inorder to measure this torque on the bearing housing IIy it is providedWith a torque-transmitting arm 35, which is rigidly secured to the sideof the housing by bolts 36 and which extends through an opening 31formed in the stationary frame 30 .so as to allow a limited movement ofthe torque arm 35 A suitable torque or force-measuring device, Fig. 2,vis connected to the arm 35 throughk a linkage which includes a socket 38on the end of the arm 35 in engagement` with a ball 39 formed on the endof a link 40 to provide a,b,a ll and socket universal joint therewith.The 4|] is provided at the other end thereof with a socket 4I arrangedin engagement with a ball 4Z on the end of an arm 43 of a bell4 crank toprovide a universal connection between the link 411 and the bell crankarm 43. The bell crank pivotally supported by a pivoty pin 44 on thestationary frame, 3D, and another arm 45 of the bell crank is rigidlysecured atA 46 toA a reverse torque mechanism which connects thevdynainometer torque arm 35` to a force-measuring or indicating device.The reverse torque mecha.-

includes a bar 41 to which the endV of the crank arm 45 is rigidlysecured at 46 and the bar 41 is arranged to engage knife edge pins 48,and 49 of the reverse torque mechanism. If torque on the bearingvhousing II tends` to rotate the bearing housing so'as` to move thetorque arm 35 to the right as viewed in Fig. 2, the bar 41 engages theknife edge 48 and exerts an upward pull on a link 50 which transmitsthis upward force through a pin 5I which en gages the lower end of aslot 52 formed in the linie 5 0, The pin 5I isrigidly secured to a lever53 which is pivotally supported by a pivot pin 54 on a mounting bracket55 which is rigidly securedtl to the stationary frame 30,.I The leverarm; 5.3v is provided with a pin 56 rigidly secured to the, end thereofopposite the pin 5I, and the upward force transmitted to the pin 5Iresults a` downward force; exerted on the pivot pin 56 which engages thelower end of a slot 51 formed in a link 58. rl-he link 58; is connectedto a spring balance scale 59 and to a balance mechanism 89 adapted tomeasure or indicate the force exertedy by the torqueI arm 35 on thevertically extending link- 58. The balance mechanism is pivotallySuspended at, BI from a supporting bar through the link 58. With thisreverse torque mechanism, the bar 4.1 transmits the force to be measuredto one o f the knife edges 48 or 49 and becomes disengaged from theother knife edge, depending upon the direction of the force transmitted'toA the bar 41 from the torque arm 35. the torque-measuring mechanismexerts a resisting force upon the bearing housing II and indicates thetorque transmitted by the shaft `Ill while preventing the rotation ofythe bearing housing HY about its axis and also provides.Y formaintaining the shaft I4- substantially in alignment with the couplinglink or shaft 2'0. However,v in order to measure the torque transmittedby the shaft I, it is lnecessary that a slight anglar movement beallowed to the bearing housing IIj and, therefore,- to thev shaft I'4`,and' the universal' connections provided by the connections to thecoupling'link 28 provide for the, transmission of torque from, thelshaft I4.' to a driven load without undesirable stress result, ing fromthe .slight angular movement 0f the shaft I4, due to the angular.movement of the bearing housing II...

The arrangement shown c an also be used to test shafts, extending inother directions from that shown., For instance,K the, downwardlyextending vertical shaft I0. might be arranged to project inA an upwarddirection from thel gear casing in order to, test a machine having avdownwardly.` ex-k tending vertical shaft. Ay dynamometer constructionsimilar to that shownv couldv also incorporate an arrangement having twohorizontally extending shaftssubstantially at right angles to each otherwherein one shaft, would bey arranged tobev connected tothe machine tobe testedv and the.. other shaft wouldV be, arranged to be connected toIan absorption machine. With this lat,- ter arrangement, Fig. 1 of thedrawing would illustrate, a; plan View, ofn theA gear box and itsconnections.. In some instances it might be found desirable to changethe ratio'of, the speeds of` the driving and, driven equi-prirent;l inwhich case,I oney of the gears: might be made; withv a. dif'- f-.eientdiameter from the other gear.. so that e maehine adapted.' i0 run at arelativelr high sneed could; he tested. bx en absorption.y generatorturning at a more convenient lower speed.

The.y measurement of-` large torques, by this type dynamemeter will:produce relai.ii/.elyr large displacements of. the afrm andrnav resultinthe transmission of a restoring force 12o-the hearing housing Itthrong-little shaft llvloy-v theeoupling link. 2.41 caused-hytheangular;displacement of; the endioffthe shaft L91. In ordente minimize orfsnb.-stentellv eliminate; this, restoring: force. which might introduce.inaccuracies in the torque measurements, the entire torque reactionmeasuring mechanism and.: the geary housing; are mounted on aturntahle64! which-.isrotatablr Sunnortedby any suitable bearing Verrengen 1enton @stationary platform base; 65;.E Anelectric motorY 6,6 is ar.-rai-iged to drivethe turntable 64` by a worm. 61 and a, segmentalgear-6asof as. te.- maintain vthe l fangen shaft I9 substantially inralignment with 'the shaft 28 of the driven load. This n'otor 66 isadapted to be operated in eitherl directionby reversal of its fieldexciting windings and is energized through a contactor 69 mounted on 5exciting windings I2 and 13, respectively, and `l() are adapted toenergize one or the other of these field exciting windings to provideexcitation to the armature 'I4 of the motor 66 in opposite directionsand thereby provide a reversing motor control responsive to thedirection of rotational 'or `15 angular displacement of the contactor69which operates in response to the rotational displacevment of thebearing housing Il. Thus, a clockwise rotation of the bearinghousing IIwould cause the contact 69 to contact the stationary E'.20

contact 'I0 to energize the motor 68 in such a manner as to cause theturntable 64 to be turned in a counterclockwise direction until contactbetween the contacts 69 and 1D isY broken by the turning of the entiremechanism together with .25

the motor 66 -for rotating the turntable 64 in a 30 direction oppositeto the rotation of the bearing housing, and thereby provides forrealignment of the shaft I9 and the driven load shaft, under whichcondition the contactor 69 opens the circuit of the motor 66. -Since thetorque reaction measuring mechanism is mounted on the same turntable asthe bearing housing Il, this rotation of the entire unit in no Wayaffects the correct reading of the torque transmitted through the geardynamometer, and .provides for an 40 accurate measurement of the torquetransmitted by the gears by the elimination of any restoring forces dueto any misalignment ofshafts.

While I have illustrated and described'a particular embodiment of myinvention, modications thereof will occur to those skilled in the art. Idesire it t0 be understood, therefore, that my invention is not to belimited to the particular arrangement disclosed, and I intend to coverall such equivalent modifications in `the appended 5o claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A dynamometer including a shaft adapted to be connected to a sourceof mechanical power,v

means for rotatably supporting said shaft, a second shaft adapted to beconnected to a driven load mounted against rotation around the axis ofsaid shaft supporting means, means including said rst-mentioned meansfor rotatably supporting said second shaft substantially at right anglesto said first-mentioned shaft, means for providing a driving .connectionbetween said two shafts, means for rotatably supporting said shaftsupporting means about the axis of said first-" mentioned shaft, andmeans for measuring the resisting torque reaction of said shaftsupporting means on said second shaft about the axis of saidfirst-mentioned shaft.

2. A dynamometer including a shaft adaptedf` to be connected to a sourceof mechanical power, means including a bearing housing for rotatablysupporting said shaft, a second shaft adapted to be connected to adriven load `by a longitudinally slidable connection, means includingsaidibearing. 75.

housing for "rotatably supporting said second shaft substantially atright angles to said firstmentionedshaft, means for providing a drivingconnection between said two shafts, means including a bearing forsupporting said bearing housing rotatably about the axis of saidfirstmentioned shaft, and means for measuring the torque reaction ofsaid shafts on said bearing housing aboutv said axis.

3. A dynamometer including a shaft adapted to be connected to a sourceof mechanical power, means including a bearing housing for rotatablylsupporting said shaft, a second shaft adapted to be connected to adriven load mounted against rotation around the axis of said bearinghousing, means including said bearing housing for rotatably supportingsaid second shaft substantially at right angles to said first-mentionedshaft, means for providing a driving connection between Ysaid twoshafts, meansfor rotatably supporting said bearing housing about theaxis of said firstmentioned shaft and substantially at right angles tosaid second shaft, and means for measuring the torque reaction of saidshafts on said bearing housing about said axis.

4. A dynamometer including a shaft adapted to be connected to a sourceof mechanical power, means including a bearing housing having a bearingarranged to support said shaft rotatably on said housing, a second shaftadapted to be connected to a driven load mounted against rotation aroundthe axis of said bearing housing,` means including said bearing housinghaving a second bearing arranged to support said second shaft rotatablyon said housing substantially at right angles to said first-mentionedshaft, means including a set of gears for providing a drivingvconnection between said two shafts, means including a bearing forrotatably supporting said bearing housing about the axis of saidfirst-mentioned shaft, and means for measuring the torque reaction ofsaid second shaft on said bearing housing about the axis of saidfirst-mentioned shaft.

5. A dynamometer including a shaft adapted to be connected to a sourceof mechanical power, means including a bearing housing having a bearingarranged to support said shaft rotatably on said housing, a second shaftadapted to be connected to a driven load by a longitudinally slidableconnection, means including said bearing housing having a second bearingarranged to support said second shaft rotatably on said housingsubstantially at right angles to said rstmentioned shaft, meansincluding a set of bevel gears for providing a driving connectionbetween Asaid two shafts, means including a bearing for supporting saidbearing housing rotatably about the axis 0f said rst-mentioned shaft andsubstantially at right angles to said second shaft, and means formeasuring the torque reaction of said second shaft on said bearinghousing about the axis of said housing supporting bearing.

6. A dynamometer including a shaft adapted to be connected to a sourceof mechanical power, means for rotatably supporting said shaft, a secondshaft adapted to be connected to a driven load mounted against rotationaround the axis of said shaft supporting means, means including saidfirst-mentioned means for rotatably supporting said second shaftsubstantially at right angles to `said first-mentioned shaft, means forprovidinga driving connection between said two shafts, frame means forrotatably supporting said shaftf supportingwmeans aboutthe axis of the7. A dynamometer including a .shaft adapted ,tohe connected to a sourceof mechanical power,

means for rotatably supporting saidl shaft, aseo,- ond shaft adaptedto.. be connected to afdriyen load mounted against. rotationiaround: theaxis, of said shaft supporting means, means includings,adf1rst.mentioned means for rotatably supporting said second shaftsubstantially at. right ansies.- tosaid first-mentioned shaft, means forpro.- viding a drivingconnection between said two shafts, framey meansfor rotatably supporting said shaft supporting means about the axis ofsaid .iirstrrnentioned shaft, meansfor measuring the resisting torquereaction of said shaftsupporting means onv said second shaft about thevaxis of said first-mentioned shaft, means including a, turntable forrotatably supporting said frame means' and said torque reactionmeasuring means, and means responsive to rotational displacement of saidshaft supporting meansl for z 'otating said turntable. for maintainingsaid second shaft substantially in alignment with said' driveni load.

8, A dynamometer including a shaft adapted tov be connected to a sourceof mechanical power, means for rotatably supporting said shaft,A asecondy shaft adapted to be connectedto a driven load mounted againstrotation around the axis of,- said shaft, supporting means, meansincluding said irstmentioned means for rotatably supporting said secondshaft, substantially at right angles to saidfirst-mentioned shaft,lmeans for providing a driving connection between said two shafts, framemeansv for rotatably supporting saidL shaftsupporting means about theaxis of said first-mentioned shaft, means for measuring `the resistingtorque reaction of said shaft supporting means on saidsecond shaft aboutthe axis of said firstmentioned shaft, means including a turntable forrotatably supportingsaid frame means and said torque reaction measuringmeans, andy means responsive to rotational displacement of said sha-ftsupporting means for driving said turntable in the opposite direction tothe rota-tion of said` shaft supporting means under the resistingtorque` reaction for maintaining said secondshaftI substantially inalignment with said driven load.

9. A dynamometer including a shaft adapted to be connected to a sourceof` mechanical power, means for-rotatably supporting said shaft, asecondy shaft adapted to be connected to a driven load mounted againstrotation around the axis of said shaft supporting means, means includingsaidv first-mentioned means for rotatablysupporting said second shaftsubstantially at right' anglesto saidfirst-mentioned shaft, means forproviding a driving connection between said two shafts, frame means forrotatably supportingsaid shaft supporting means. about the, axis of saidfirst-mentioned shaft, means for measuring the resisting torque reactionof said shaft'. supporting means on said second shaft about: the. axisof said first-mentioned shaft, means including a vturntable forrotatably supporting said frame means and said torque reaction`measuring means, means including a motor for rotatably driying saidturntable, and means.- including a1 reyersing control for controllingsaidmotorforadrivingfsaid,

'turntable the: oonosite direction. to the. rotation .of said shaft,supporting means under the res-ist- -ing tongue V.reaction ,formaintaining said second ,shaftsubstantially' inalignment with saiddriven load.

1Qa` A, dynamgmeter' including a shaft adapted tabeconneoted to a Sourceof mechanical power, xneans, including a bearing housing for rotatablysupporting said shaft, a second shaft adapted to be` coni-iectedV by alongitudinally slidable connectiqn to4 a driven load mounted againstrotation, around ther axis of said bearing housing, means, includingsaidbearing housing for rotatably supporting said second shaftsubstantially at right angles .to said first-mentioned shaft, means; for`providing a driving connection between said, twoishafts, frame meansfor rotatably supporting lsaid bearing housing about the axis of. saidrstrmentioned shaft, means for meas,- uring; the .torque reaction ofsaid second shaft on said, bearing housing about the axis of said,Erst-mentioned shaft, and means for rotatably Slipportingv said ,framemeans, and said torque re,- action measuring means and for maintainingsaid second shaft substantially in alignment with said driven load.

1L. A, dynamometer including a shaft adapted to. be connected, to, asource of mechanical power, means .including a bearing housing forrotatably .supporting said, shaft,v a second shaft adapted to 'deconnected to, a driven load mounted against rotation around, the. axisof said hearing housing, means including-saidhearing housing forrotatably, supporting said second shaft substantially at riehtaneles. tosaid 'first-mentioned shaft, means for proyidinsa. driving connectionbetween said twoA shafts, frame, means for rotatably supportins saidhearing housing about the axis of said first-mentioned shaft, means formeasuring the torque reaction of said second shaft on said bearinghousing about the axis of said'st-mentioned shaft, 1ne ans for rotatablysupporting said frame means aIldsaidtorque reaction measuring means, andmeans. for rotating said last-mentioned rotatable ysupporting means form,aintainingl said lsecond Shaft .substantially in alignment with said-ablysupportingsaid second shaft substantially at right ang-les tosaidfirst-mentioned shaft, means-forproviding a driving connectionbetween saidtwovshaf-ts; frame meansv for rotatably supporting saidbee-ringhousing about the axisof 60' said rst-mentioned shaft, means formeasuring"l 'the torque' reaction ofsaidv second shaft on said bearinghousing about the axis of said first-men- Vtionedl shaft, means: forYrotatably supporting said means; including; a. bearing; housing forrotatably supporting` said: shaft, av second shaft adapted to bevconnected; by a longitudinally slidablel connection,v toa, driven.loadmounted against rotation around .the existo .said bearing housine-,-means 9 including said bearing housing for rotatably supporting saidsecond shaft substantially at right angles to said first-mentionedshaft, means for providing a, driving connection between said twoshafts, frame means for rotatably supporting said bearing housing aboutthe axis of said rst-mentioned shaft, means for measuring the torque reaction of said second shaft on said bearing housing about the `axis ofsaid first-mentioned shaft, and means for rotatably supporting saidframe means and said torque reaction measuring means responsive torotational displacement of said bearing housing for maintaining saidsecond shaft substantially in alignment with said driven load.

14. A dynamometer including a shaft adapted to be connected to a sourceof mechanical power, means including a, bearing housing for rotatablysupporting said shaft, a second shaft adapted to be connected by alongitudinally slidable connection to a driven load mounted againstrotation around the axis of said bearing housing, means including saidbearing housing for rotatably supporting said second shaft substantiallyat right angles to said first-mentioned shaft, means for providing adriving connection between said two shafts, frame means for rotatablysupporting said bearing housing about the axis of said first-menn tionedshaft, means for measuring the torque reaction of said second shaft onsaid bearing housing about the axis of said rst-mentioned shaft, meansfor rotatably supporting said frame means and said torque reactionmeasuring means, means including a motor for rotating saidlast-mentioned rotatable supporting means, and motor control meansresponsive to rotational displacement of said bearing housing formaintaining said second shaft substantially in alignment with saiddriven load.

HAROLD M. MARTIN.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,557,956 Zubaty Oct. 20, 19251,785,243 Bewley Dec. 16, 1930 1,789,650 Graham et al Jan. 20, 19312,079,751 Tilden May 11, 1937 2,121,623 Bobek June 21, 1938 2,254,575Kronquest Sept. 2, 1941 2,391,024 Martin Dec. 18, 1945

